Making Christmas cactuses bloom; saffron crocuses, azaleas

October 19, 1983

Q Last December I was given a showy Christmas cactus and would like to know how to make it bloom again this year. What should we do? If you have been able to keep your plant in a room with good light and where nighttime temperatures have been between 55 and 60 degrees F. since mid-September, it will likely bloom in time for the holidays.

Folks who cannot provide this temperature range have to resort to treatment that is similar to that for poinsettias.

Starting in mid-September, the plant must get from 13 to 14 hours of complete darkness. Thus, it must be shaded daily from light with a dark cloth or bag from about 5 p.m. until, say, 7 the next morning until late November. The plant soil must be kept from going bone dry until little buds are seen on the ends of the stems. Then it should be watered enough to keep the soil moist, but not soggy.

Q We have moved to the country near a poultry farm. The owners have offered us some manure for our garden, which is rather claylike. Should we spread it on top of the soil for the winter or work it right in? Also, how much can we use at a time? The poultry manure will help the composition of your soil.

If you spread it this fall and then work it into the soil in the spring, it will not burn the plants. Use one bushel per 100 square feet of soil.

Q My husband says a severe winter would help us eliminate some of the insects , but I maintain the insects can survive almost anything. Who is right? Severe winters can delay the hatching of some insects, but they have little effect on the population of most species where winter is a normal fact of life.

Severity can have an effect on insects that are native to Southern areas; but just as with pesticides, the survivors breed generations which are more resistant to the conditions.

Many species overwinter as eggs or larvae while others may produce an antifreeze chemical. Severe cold, coupled with strong winds, can have an impact on exposed egg masses.

Q An article on spices and herbs mentioned that saffron comes from a lavender fall-blooming crocus. Is there the lavender one calls ''mystery lily'' which will bloom even before it is planted?

The answer is no. The mystery lily is colchicum, often mistakenly called autumn crocus (bulbs are toxic if ingested).

True saffron crocus are short-stemmed and their bulbs (corms), flowers, and leaves resemble those of other crocuses, except the leaves have a white stripe and they bloom in the fall. Each bloom has three threadlike red stigmas coming from the center. These are the saffron, which should be removed with tweezers and laid on a paper towel in subdued light to dry.

Q When we planted our azaleas we put peatmoss in the hole around the roots. Now the leaves are getting faded-looking as if the green had washed out. What will bring back the color? Continued acidity cannot be assured merely by adding peatmoss at planting time, especially if the soil is alkaline (sweet).

There are excellent preparations for acidifying soils for acid-loving plants. They can be found in garden stores and the clerks should be familiar with them. But if you do not have favorable conditions, such as a moist, humusy soil with a pH somewhere near 4.5 to 6.5, as well as semi-shade, you should grow plants that will tolerate the conditions you do have.